为了解固城湖围垦区不同池塘的河蟹养殖环境效应并筛选出适宜的生态养殖模式,对河蟹养殖周期内不同养殖池塘的养殖情况和水环境进行跟踪研究,并构建模型估算养殖容量.结果表明,养殖周期内现有养殖模式的池塘和取水河道水质大多为GB 3838-2002《地表水环境质量标准》中的Ⅳ类和Ⅴ类水,明显劣于固城湖水质(Ⅲ类水),其中最主要的污染因子为TN和TP；池塘的浮游植物、浮游动物和底栖动物的群落结构简单,优势种分别为隐藻、秀体溞及环棱螺,且浮游动物Margalef丰富度指数与河蟹养殖产出呈显著正相关(P＜0.05)；基于现有养殖模式,河蟹的最大养殖容量为9855只hm-2.综合考虑养殖池塘环境、经济效益及养殖容量等因素,认为固城湖围垦区池塘河蟹的适宜生态养殖模式为:蟹苗投放密度(9000±750)只·hm-2；饵料系数0.47 ～0.53;水草覆盖度约70％(其中苦草40％,伊乐藻20％,轮叶黑藻10％)；螺类投放量6 000 ～7500 kg·hm-2.%In order to study environmental effects of crab culture in different ponds in reclamation zones of the Gucheng Lake and screen an optimal ecological pattern of crab culturing, the operation of crab culture and variation of the water environment during the period were monitored and a model was constructed to estimate the carrying capacity of the ponds. Results show that under the current pattern of crab culturing, the waters in the ponds and the water supplying rivers fell in Grade Ⅳ and Ⅴ of the "Standard for Surface Water Environmental Quality" (GB 3838 -2002), and were obviously lower than that in the Gucheng Lake, which was in Grade Ⅲ. In the former, total nitrogen(TN) and total phosphorus(TP) were the main polluting factors. In the ponds, the community structures of phytoplankton, zooplankton and benthos were simple, and dominated mainly by Cryptorrwnas ehrenberg, Diapharwsoma and Bellamya. The Margalef species richness index (D) was significantly and positively related with crab output (P<0.05). Based on the current pattern, the largest crab carrying capacity of the ponds is 9 855 ind · hm-2. Based on comparative analysis of the ponds under the current pattern and under the pattern of comprehensive crab culture in pond environment, economic benefit and carrying capacity, an optimal ecological pattern of crab culture is recommended to be (9 000 ± 750) ind · hm-2 in juvenile crab input rate, 0.47 -0.53 in food coefficient, about 70% in aquatic plant coverage (Vallisneria spiraslis 40%, Elodea nuttallii 20%, H. verti-callata 10%); and 6 000 - 7 500 kg·hm-2 in snail input rate.
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